Furnace with drain



Jan. 21, 1930. CROCKER 1,744,694

FURNACE WITH DRAIN Filed May 15. 1928 1810922303.- Per-0.161202 .B.Crocier by 5 7 5%ya Patented Jan. 21-, 1930 UNITED STATES PATENT osricaPERCIVAL B. OROCKER, TAUNTON, MASSACHUSETTS, ASSIGNOR TO THE SEN-TRYCOMPANY, OF TAUNTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTSFURNACE WITH DRAIN Application filed May 15,

This invention relates to furnaces of the type wherein material in asuitable container is reduced to a fluid state, and the object is toprovide improved means for discharging from the furnace any leakage fromthe container.

My invention will be well understood from the following description ofthe illustrative embodiment thereof shown by way of example in theaccompanying drawing which shows in side elevation an electricallyheated pot furnace with part broken away to disclose the interior.

Referring to the drawing, the form of furnace in which I have shown theprinciples of my invention embodied by way of example comprises a wall 3of suitable refractory material defining an interior heating chamber 5in which may be suspended the container or pct 7 for the material to beheated, the top of this pot being covered in the example shown by themovable cover sections 9. The pot may be heated by means of electricresistance elements 11 disposed adjacent the interior side walls of thechamber. Due to the thickness of the walls 3 and to the material ofwhich they are composed, the outside of the furnace is relatively cool.

In case the pot leaks it is desirable to discharge the leakage from theinterior of the furnace, and herein the bottom wall thereof is dished asindicated at 13 so that any liquid material falling into the chamberwill gravitate toward a central drain passage 15 opening through thebottom wall of the furnace. It will be understood, however, that thematerial which is used is not liquid at ordinary temperatures and sooncongeals or solidifies. Thus, if an ordinary opening were providedthrough which the leakage might drip, as it approached the outside ofthe furnace and a cooler region, the material would solidify and adhereto the wall of the opening and tend to plug the same up. My inventionpare5 ticularly provides for preventing the material from solidifying inthe drain passage.

In the form of my invention shown this purpose is attained in two ways;first, by preventing material from making contact with the wallof thepassage in the cooler part there- 1928. Serial No. 277,894.

of adjacent the discharge end, and, second, by minimizing thetemperature drop along the wall of the passage. These results are bothconveniently obtained by the arrangement shown in which the passage 15is provided with a metal bushing 17 lining the walls thereof which,being of relatively high heat conductivity, will maintain the dischargeend of the passage relatively warm Without material loss of heat fromthe interior of the furnace. Quite apart, however, from heating the wallof the discharge passage in this manner, I preferably provide meanswhereby contact of the leaking material therewith will be at mostaccidental, and I have herein shown integrally formed at the upperportion of the bushing 17 a dished drain plate 19 of annu lar form intowhich the liquid material is discharged from the sloping surface 13 andhaving a central opening 21 through which the material falls, thisopening 21 being conveniently axially. aligned with the bushing 17. Thecross-sectional area of the bore of the bushing 17 is considerablygreater than that of the opening 21 so that the inner portion of thedished drain plate provides an overhanging lip or flange and liquidmaterial discharged over this flange and dripping over the edge thereofwill fall freely through the bore of the bushing away from the wallsthereof and, even if congealing while falling, will drop freely in thedischarge passage like a drop of rain or a pellet in a shot towerwithout coming into Contact with the wall of such passage in such manneras would permit it to freeze thereon. In case any material should backover and around the edge of the lip under certain conditions ofdischarge, the relatively high temperature of the bushing 17 at thelower or discharge end thereof due to its good heat conducting qualitieswill tend to prevent adherence of the solidifying material to the wallin such manner as to obstruct the drain passage.

I am aware that the invention may be embodied in other specific formswithout departing from the spirit or essential attributes thereof, and Itherefore desire the present embodiment to be considered in all respectsas illustrative and not restrictive reference being had to the appendedclaims rather than to the foregoing description to indicate the scope ofthe invention.

Claims:

1. A furnace of the class described having a heating chamber and a potsuspended therein d spaced fr m th n r wall thetee a drain passagethrough said Wall, said Wall being shaped to direct thereover leakagefrom the pot to said drain opening, said passage having a metal bushingprovided at its upper end With an inwardly projecting and down:

Wardly sloping flange.

2. A furnace of the class described having a heating chamber and a potsuspended therein nd paced t am he nne w ll thereo a d ain a ess t ugh ad. ll, said ell bei g S p t d t ther o er eakage m the pot to said drainopening, said passage having therein remote from its discharge and an oer ang ng lie o di ct s ch leak ge ever t e edge hereo cl ar of t e We la the passage- 3- A furna e f t e lass d cribed havi a all es s ing thes ap f hea th ret r ugh and d fining an n i at ng hamb ecei ing a meling po in spac d relation o he bottom therec'f, t e e l a t e bo t m osaid cham e av g a drain p s sage th ethr gh, d b m b ing hap tadirect,leak g QWa s d pa age nd means to direct such leakage to the central ption. f said p s ag 0 fall f ee y th rethre gh c a f s el 6}. In afurnace of the class described hav. g a h a ing chamber and a p t su ped therein in spaced relation to the bottom thereof, a dished drain platein the bottom 0f the chamber, said bottom being formed to direct leakagefrom the pot to said plate, said plate having a centrally located openinand a drain passage through the bottom of the furna e b h id openi g and9 gr ats; crosssectional area,

A furnace of the class described having a heating chamber and a potsuspended therein in spaced relation to the bottom thereof, t chamb i ga rai pa sage a d th interior wall thereof being shaped to directleakage from the pot to said passage, said pas ag av ng a bush ng otherm l y n-

